Armband for iPod nano 4th generation for use with Nike+ Receiver (fits ipod nano 4G with a connected Nike + iPod Sport Kit Receiver) Holds 4th generation nano with a connected Nike + iPod Sport Kit Receiver (Will not work for 5G nano) Ultra slim and lightweight neoprene armband fully covers 4th gen iPod nano Hidden pocket holds key or money; Securely stores and manages earphone cord Clear, protective window cover with full navigational control Comfortable and flexible armband adjusts to fit arms 8" to 16" and an Armband Extender is available for larger arm sizes (see EX3 sold separately); Reflective material for nighttime safety.